Problem: In a geometric progression whose terms are positive, any term is equal to the sum of the next two following terms. Then the common ratio is
Answer Choices:
A. 1
B. about 25​​
C. 25​−1​
D. 21−5​​
E. 5​2​
Solution:
arn=arn+1+arn+2;∴r2+r=1;∴r=(5​−1)/2.